I finished my Asteroids-clone in XNA.

Here's the ccgame-file.

Asteroids.ccgame

You'll need the XNA-framework installed.

Screenshots:

Looks pretty tacky, but I didn't want to focus on the graphics here. I made it to learn C#. The reason I wanted to learn C# (again) was DesertFox's little XNA-tutorial, which he posted here not too long ago. This time I've finally gotten further with it.